FrontEngineDragsters.Org Forum
Technical => Spud Miller's Cave => Topic started by: matt b on July 30, 2018, 12:58:48 PM
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Hi y'all. Got the 406 in my MW car fired up this weekend. 406 / 3 piece Hilborn / DSR pump / 36 degrees timing / 115 main bypass/ 90 high speed at 50# on alcohol.
Started with BV leaked to 25% - small adjustments leaner have it idling pretty well and it's crisp on the throttle once I blow it out.
Passenger side cylinders seem very fat - 2/4/6/8 - most particularly #2 and #6. They are blowing lots of raw fuel at idle. They clean out fine when I hit the throttle but they appear to be very very rich.
Checked nozzles last night (clean), checked valve lash (all good at .02), fresh spark plugs. Going to check / gauge butterfly adjustment on that bank tonight after work.
Anybody wanna take a stab at why it's really good on one bank and super fat on the other....got butterfly adjustment in my head....what else might I be missing?
Thanks in advance!
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Throttle plates side to side adjustment is off ! One side is open more than the other !
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Thanks - I’ve breathed enough alcohol fumes this weekend to be second guessing myself!
Will check and set them tonight and report back.
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Stack injection is difficult to get even out!
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I used to use a uni sync tool to adjust them
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Phone won’t let me copy a link, but spud has an article on his site called belligerent butterfly’s that should help.
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Phone won’t let me copy a link, but spud has an article on his site called belligerent butterfly’s that should help.
Here you go
http://www.fuelinjectionent.com/butterflies.php
My phone worked ;D
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Thanks for that!
Glad to report success - reset butterflies, adjusted BV to 25% and fired right up. Went about three flats leaner and while it's not quite perfect it's 100% better than it was.
Now that I've heard it run and filled my shop with methanol fumes....out it comes. Needs a new pan gasket and it's finally time for chassis paint, re-cert and assembly!
Thanks all.
MB
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Get the cert prior to paint just in case!
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Yah - absolutely!